The looming Russian/Ukrainian conflict has little to do with U.S. interests or national defense. The United States of America is not synonymous with "World Police". Foreign affairs that do not directly impact our national defense are not of our concern. Russia has entered Ukraine, not U.S. territory, and we should remain staunchly apart from any aggression toward either state.
The military of this nation is still involved in two wars that have been going on for over ten years. We do not need to further involve ourselves in foreign conflicts that have nothing to do with us.